California provided several ports and points of entry for immigrants. San Francisco, in the north, is the largest. In the south, at the mouth of the Los Angeles Harbor are the ports of San Pedro, Wilmington, and Los Angeles; however, these are considered one port of entry in passenger arrivals by sea. Southern land points of entry include San Ysidro, Campo, and Tecate in San Diego County, and Andrade in Imperial County from Mexico.

The California State Library has microfilms of the National Archives arrivals lists, and these are also available on microfilm at the FHL. Many immigrants in this period were from China and Japan, but a good number were from Europe, Australia, India, Chile, Peru, and elsewhere. Below is a list of NARA resources and some compilations.

Other record types can serve to document immigrants from outside the United States and emigrants from within the United States, such as records for the Russian Consular in San Francisco (1862–1928), which document Jews, Poles, Ukranians, Lithuanians, and Finns, among others.

Ancestry.com has a database that is an index to passenger and crew lists of ships and some airplanes arriving at Los Angeles, San Pedro, San Francisco, and Ventura, California between 1893 and 1957. In addition, the names found in the index are linked to actual images of the passenger and crew lists, copied from the National Archives and Records Administration (NARA) microfilm (see Source Information for specific microfilm series and roll information). Subscribers can access this database at California Passenger and Crew Lists, 1893-1957.